Catalytic reactions of hydrocarbons over Pt-Pd alloys--3. Skeletal reactions of n-pentane and n-hexane over Pt-Pd/Sio/sub 2/ catalysts

Journal Article · Sun Jun 01 00:00:00 EDT 1980 · J. Catal.; (United States)

OSTI ID:6456489

Karpinski, Z; Koscielski, T

The isomerization, cyclization, and hydrogenolysis kinetics of n-pentane and n-hexane were studied on dispersed silica-supported 1% alloy consisting of 0-100% palladium/platinum. The catalysts were calcined for 25 hr at 600/sup 0/C prior to reduction or only reduced in hydrogen at 400/sup 0/C. The surface composition was probably similar to bulk composition. The catalytic activity vs. composition curves were similar for precalcined and uncalcined catalysts and for various reaction temperatures (300/sup 0/-360/sup 0/C). For n-pentane, hydrogenolysis was higher on palladium than on platinum or low-palladium alloys but more selective towards butane on platinum; isomerization decreased with increasing palladium content; and cyclization went through a maximum on alloy catalysts. The reaction patterns were similar with n-hexane, except that precalcination of the catalyst suppressed cyclization to methylcyclopentane and benzene. The catalysts underwent a poisoning process which was generally highest at the higher temperatures and higher palladium contents. The results were compared with results obtained on Pt-Pd foil and mechanisms were discussed.

• Research Organization: Institute Physical Chemical, Polish Academy Science
• OSTI ID: 6456489
• Journal Information: J. Catal.; (United States), Vol. 63:2
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CATALYSTS
CHEMICAL COMPOSITION
COMPARATIVE EVALUATIONS
HEXANE
DEHYDROCYCLIZATION
ISOMERIZATION
PALLADIUM ALLOYS
CATALYTIC EFFECTS
PENTANE
PLATINUM ALLOYS
CHEMICAL REACTION KINETICS
POISONING
TEMPERATURE EFFECTS
ALKANES
ALLOYS
CHEMICAL REACTIONS
HYDROCARBONS
KINETICS
ORGANIC COMPOUNDS
PLATINUM METAL ALLOYS
REACTION KINETICS
400301* - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)
400201 - Chemical & Physicochemical Properties